"Today's news is a turning point for the country's energy future. Shale gas has the potential to create jobs, generate tax revenues, reduce our reliance on imported gas, and improve our balance of payments," chief executive Francis Egan said in a statement.

In an interview with CNN, Egan insisted that fracking could be done "safely and sensibly" in Britain and that there are huge reserves to be exploited.

The company believes there is about 200 trillion cubic feet of gas under the ground just within its license area in Lancashire. To put that figure into context, the United Kingdom uses about 3 trillion cubic feet of gas a year, Egan said.

He said he could understand that people are concerned but pointed out that the two tremors triggered in April and May of last year "were not major events."

The website of the British Geological Survey shows it has recorded nine tremors of a similar magnitude in the past two months, he said.

"They are not life-threatening events or damage-inducing events, but they do cause concern, so as a consequence the fracking was suspended," he said.

Cuadrilla has done a lot of work since then, he said, including carrying out 3-D mapping of the area. Extensive arrays will be installed around the wells to monitor seismic activity, he added.

As for concerns about how the liquids used in fracking will affect water supplies, Egan said the company uses only one friction-reducing chemical, in small quantities. He said it is not hazardous and the government oversees its use.

The strong regulatory environment in the United Kingdom "will stand us in good stead," Egan said, although he acknowledged it would mean the pace of exploration may be slower than in the United States.

The process has sparked opposition in the United Kingdom.

The government announcement marks "the start of a major battle over what sort of world we will leave to our children," said Lilly Morse, an activist with the Frack Off campaign group.

"The government and industry's promises of cheap, abundant gas are deluded," she said, adding that in the United States, "the gas bubble has already burst" and some fracking companies are on the verge of bankruptcy.

"The government's strategy of relying on fracking to fuel a new wave of gas-fired power stations is utterly insane. Fracking is dirty, destructive and extremely expensive, and could never deliver the quantities of gas envisaged."